/
Euler_027.php
106 lines (98 loc) · 2.18 KB
/
Euler_027.php
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<?php
function is_prime($num)
{
if(!($num - 1) || $num % 2 == 0 && $num!=2)
return false;
if($num == 2)
return true;
for($i = 3; $i <= sqrt($num); $i+=2) {
if($num % $i == 0) {
return false;
}
}
return true;
}
function check_prime($number_1,$number_2,$type)
{
$x = 0;
if($type == 1)
{
$sign_1 = 1;
$sign_2 = 1;
}
elseif($type == 2)
{
$sign_1 = -1;
$sign_2 = 1;
}
elseif($type == 3)
{
$sign_1 = 1;
$sign_2 = -1;
}
elseif($type == 4)
{
$sign_1 = -1;
$sign_2 = -1;
}
do
{
$check = ($x * $x) + ($sign_1 * $number_1 * $x) + ($sign_2 * $number_2);
$test = is_prime(abs($check));
if($test)
{
$x++;
}
else
return $x;
}
while($flag!=X);
}
echo "<table>";
$greatest[0]=0;
$greatest[1]=0;
$greatest[2]=0;
for($a=0;$a<1000;$a++)
{
for($b=0;$b<1000;$b++)
{
$test = is_prime($b);
if($test)
{
$number = check_prime($a,$b,1);
//echo "<tr><td>".$a."</td><td>".$b."</td><td>".$number."</td></tr>";
if($number > $greatest[2])
{
$greatest[0]=$a;
$greatest[1]=$b;
$greatest[2]=$number;
}
$number = check_prime($a,$b,2);
//echo "<tr><td>".($a*-1)."</td><td>".$b."</td><td>".$number."</td></tr>";
if($number > $greatest[2])
{
$greatest[0]=($a*-1);
$greatest[1]=$b;
$greatest[2]=$number;
}
$number = check_prime($a,$b,3);
//echo "<tr><td>".$a."</td><td>".($b*-1)."</td><td>".$number."</td></tr>";
if($number > $greatest[2])
{
$greatest[0]=$a;
$greatest[1]=($b*-1);
$greatest[2]=$number;
}
$number = check_prime($a,$b,4);
//echo "<tr><td>".($a*-1)."</td><td>".($b*-1)."</td><td>".$number."</td></tr>";
if($number > $greatest[2])
{
$greatest[0]=($a*-1);
$greatest[1]=($b*-1);
$greatest[2]=$number;
}
}
}
}
print_r($greatest);
?>